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Jan 19, 2024

Discovery of new ultra-large cosmic structure challenges our understanding of the universe

Posted by in category: cosmology

The discovery of a second ultra-large structure in the remote universe has further challenged some of the basic assumptions about cosmology.

The Big Ring in the Sky is 9.2 billion light-years from Earth. It has a diameter of about 1.3 billion light-years, and a circumference of about 4 billion light-years. If we could step outside and see it directly, the diameter of the Big Ring would need about 15 full moons to cover it.

It is the second ultra-large structure discovered by University of Central Lancashire (UCLan) Ph.D. student Alexia Lopez who, two years ago, also discovered the Giant Arc in the Sky. Remarkably, the Big Ring and the Giant Arc, which is 3.3 billion light-years across, are in the same cosmological neighborhood—they are seen at the same distance, at the same cosmic time, and are only 12 degrees apart in the sky.

Jan 19, 2024

In New Experiment, Young Children Destroy AI at Basic Tasks

Posted by in categories: innovation, robotics/AI

A study pitting human children against large language models in basic reasoning problems revealed AIs to have one big blind spot: innovation.

Jan 19, 2024

Arizona State students will get their own ChatGPT-powered tutors as OpenAI partners with the university

Posted by in category: robotics/AI

On Thursday, OpenAI and ASU announced the first-of-its-kind partnership, which has reportedly been in the works for six months.

Students, professors, and researchers are set to get access to the tech in February. The university plans to build personalized AI tutors and avatars for students and expand its prompt engineering course.

In a press release, Arizona State University said the partnership would set a new precedent for how universities “enhance learning, creativity and student outcomes.”

Jan 19, 2024

Unlocking the secrets of quasicrystal magnetism: Revealing a novel magnetic phase diagram

Posted by in categories: particle physics, quantum physics

Quasicrystals are intermetallic materials that have garnered significant attention from researchers aiming to advance condensed matter physics understanding. Unlike normal crystals, in which atoms are arranged in an ordered repeating pattern, quasicrystals have non-repeating ordered patterns of atoms.

Their unique structure leads to many exotic and interesting properties, which are particularly useful for practical applications in spintronics and magnetic refrigeration.

A unique quasicrystal variant, known as the Tsai-type icosahedral quasicrystal (iQC) and their cubic approximant crystals (ACs), display intriguing characteristics. These include long-range ferromagnetic (FM) and anti-ferromagnetic (AFM) orders, as well as unconventional quantum critical phenomenon, to name a few.

Jan 19, 2024

Typo in telescope coordinates reveals one of the faintest galaxies in the known universe

Posted by in category: space

Astronomers accidentally uncovered an extremely dark primordial galaxy — one of the faintest objects in the universe — because of a typo in their telescope coordinates.

Jan 19, 2024

Quantum Approaches to Consciousness

Posted by in categories: neuroscience, quantum physics

It is widely accepted that consciousness or, more generally, mental activity is in some way correlated to the behavior of the material brain. Since quantum theory is the most fundamental theory of matter that is currently available, it is a legitimate question to ask whether quantum theory can help us to understand consciousness. Several approaches answering this question affirmatively, proposed in recent decades, will be surveyed. There are three basic types of corresponding approaches: consciousness is a manifestation of quantum processes in the brain, quantum concepts are used to understand consciousness without referring to brain activity, and matter and consciousness are regarded as dual aspects of one underlying reality. Major contemporary variants of these quantum-inspired approaches will be discussed.

Jan 19, 2024

Are tiny black holes hiding within giant stars?

Posted by in category: cosmology

Phenomenon could account for universe’s mysterious dark matter.

Jan 19, 2024

The neural origin for asymmetric coding of surface color in the primate visual cortex

Posted by in category: neuroscience

Whether end-spectral bias for red and blue in the visual cortex inherits from the pre-cortical stage or emerges within V1 remains incompletely understood. Here, the authors revealed a feedforward mechanism of end-spectral bias which is mainly transmitted through parvocellular pathway.

Jan 19, 2024

High-temperature tolerant TaOX/HfO2 self-rectifying memristor array with robust retention and ultra-low switching energy

Posted by in category: computing

Heat resistant mimresister at room temperature.


Due to the heat generation during operations in high-density three-dimensional (3D) integrated chips, a high-temperature tolerant and high-performance self-rectifying memristor (SRM) is a promising candidate for 3D integration. Here, we investigated the high-temperature characteristics of Ta/TaOX/HfO2/Pt SRMs with a 250 nm feature size in an 8 × 8 crossbar array (CBA). The SRMs exhibit high uniformity and can be operated repeatedly at Set (4 V/2 μs) and Reset (−2 V/1 μs) pulses for more than 104 cycles resulting in ultra-low switching energy (5.86 aJ for Set and 77.2 aJ for Reset). High yield of the array indicates the reliable preparation processes. Remarkably, the CBA is capable of stably resistive switching at high temperatures from 300 to 475 K. At 300 K, the SRM shows large nonlinearity (NL, ∼1.4 × 104) and rectification ratio (RR, ∼8.8 × 103) as well as high scalability (330 Mbit); at 475 K, the NL and RR of the SRM can still maintain above 400, and the scalability still reaches 71 Kbit. Moreover, our SRM passed a high-temperature retention test of over 5 × 104 s at 438 K. Segmented fittings of the I–V curves of the SRM at different temperatures were performed, concluding that large NL and RR attributed to the Schottky barriers at TaOX/HfO2 and Pt/HfO2 interfaces, respectively. Our work furnishes a feasible solution for high-density 3D integrated memristors in high-temperature application scenarios represented by automotive-grade chips.

Jan 19, 2024

Ferroelectric artificial synapses for high-performance neuromorphic computing: Status, prospects, and challenges

Posted by in categories: computing, electronics

Neuromorphic computing provides alternative hardware architectures with high computational efficiencies and low energy consumption by simulating the working principles of the brain with artificial neurons and synapses as building blocks. This process helps overcome the insurmountable speed barrier and high power consumption from conventional von Neumann computer architectures. Among the emerging neuromorphic electronic devices, ferroelectric-based artificial synapses have attracted extensive interest for their good controllability, deterministic resistance switching, large output signal dynamic range, and excellent retention. This Perspective briefly reviews the recent progress of two-and three-terminal ferroelectric artificial synapses represented by ferroelectric tunnel junctions and ferroelectric field effect transistors, respectively. The structure and operational mechanism of the devices are described, and existing issues inhibiting high-performance synaptic devices and corresponding solutions are discussed, including the linearity and symmetry of synaptic weight updates, power consumption, and device miniaturization. Functions required for advanced neuromorphic systems, such as multimodal and multi-timescale synaptic plasticity, are also summarized. Finally, the remaining challenges in ferroelectric synapses and possible countermeasures are outlined.

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